After an HVDC relay is powered, a pushrod fixed on a moving iron core might radially deflect toward a magnetic conductive cylinder due to a magnetic force. That is, a certain included angle is generated between an axis of the pushrod and an axis of the magnetic conductive cylinder, and thus a certain included angle is also generated between an axis of the moving iron core and an axis of the magnetic conductive cylinder. As a result, when the moving iron core and the pushrod are moving upward and downward, a frictional force between the two and an inner wall of the magnetic conductive cylinder is increased. On one hand, the sensibility of the relay will be decreased, resulting in delayed response. On the other hand, the power consumption of the relay will be increased, and the relay will even be burned out.